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At least 1,351 records · Page 75
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on ClF3 by Materials Project

ClF3 is High Pressure (4-7GPa) Tellurium structured and crystallizes in the orthorhombic Pnma space group. The structure is zero-dimensional and consists of four ClF3 clusters. Cl is bonded in a T-shaped geometry to three F atoms. There is one shorter (1.64 Å) and two longer (1.75 Å) Cl–F bond length. There are two inequivalent F sites. In the first F site, F is bonded in a single-bond geometry to one Cl atom. In the second F site, F is bonded in a single-bond geometry to one Cl atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on C3N2 by Materials Project

C3N2 is alpha Po structured and crystallizes in the cubic P-43m space group. The structure is zero-dimensional and consists of one C3N2 cluster. C2+ is bonded in a bent 120 degrees geometry to two N3- atoms. There is one shorter (1.43 Å) and one longer (1.44 Å) C–N bond length. There are two inequivalent N3- sites. In the first N3- site, N3- is bonded in a trigonal planar geometry to three equivalent C2+ atoms. In the second N3- site, N3- is bonded in a trigonal planar geometry to three equivalent C2+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hg3(ClO5)2 by Materials Project

Hg3O2(ClO4)2 crystallizes in the monoclinic C2/c space group. The structure is zero-dimensional and consists of eight ClO4 clusters and four Hg3O2 clusters. In each ClO4 cluster, there are four inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.46 Å. In the second O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.46 Å. In the third O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.46 Å. In the fourth O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.47 Å. Cl is bonded in a tetrahedral geometry to four O atoms. In each Hg3O2 cluster, there are two inequivalent Hg sites. In the first Hg site, Hg is bonded in a single-bond geometry to one O atom. The Hg–O bond length is 2.13 Å. In the second Hg site, Hg is bonded in a linear geometry to two equivalent O atoms. Both Hg–O bond lengths are 1.97 Å. O is bonded in a bent 120 degrees geometry to two Hg atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on SrO4 by Materials Project

SrO4 is Cyanogen Chloride-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is zero-dimensional and consists of one SrO4 cluster. Sr is bonded in a linear geometry to two equivalent O atoms. Both Sr–O bond lengths are 2.19 Å. There are two inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one O atom. The O–O bond length is 1.32 Å. In the second O site, O is bonded in a distorted single-bond geometry to one Sr and one O atom.

36 MATERIALS SCIENCE↗
NASA NTRS1996

The Angular Power Spectrum of BATSE 3B Gamma-Ray Bursts

We compute the angular power spectrum C(sub l) from the BATSE 3B catalog of 1122 gamma-ray bursts and find no evidence for clustering on any scale. These constraints bridge the entire range from small scales (which probe source clustering and burst repetition) to the largest scales (which constrain possible anisotropics from the Galactic halo or from nearby cosmological large-scale structures). We develop an analysis technique that takes the angular position errors into account. For specific clustering or repetition models, strong upper limits can be obtained down to scales l approx. equal to 30, corresponding to a couple of degrees on the sky. The minimum-variance burst weighting that we employ is visualized graphically as an all-sky map in which each burst is smeared out by an amount corresponding to its position uncertainty. We also present separate bandpass-filtered sky maps for the quadrupole term and for the multipole ranges l = 3-10 and l = 11-30, so that the fluctuations on different angular scales can be inspected separately for visual features such as localized 'hot spots' or structures aligned with the Galactic plane. These filtered maps reveal no apparent deviations from isotropy.

Tegmark, Max↗
DOE OSTI2020

Materials Data on P2H19C6I2NCl4 by Materials Project

C6P2NH19ICl2ICl2 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four C6P2NH19ICl2 clusters and four ICl2 clusters. In each C6P2NH19ICl2 cluster, there are six inequivalent C+3.33- sites. In the first C+3.33- site, C+3.33- is bonded to one P5+ and three H1+ atoms to form distorted corner-sharing CPH3 tetrahedra. The C–P bond length is 1.78 Å. All C–H bond lengths are 1.10 Å. In the second C+3.33- site, C+3.33- is bonded to one P5+ and three H1+ atoms to form distorted corner-sharing CPH3 tetrahedra. The C–P bond length is 1.79 Å. All C–H bond lengths are 1.10 Å. In the third C+3.33- site, C+3.33- is bonded to one P5+ and three H1+ atoms to form distorted corner-sharing CPH3 tetrahedra. The C–P bond length is 1.79 Å. All C–H bond lengths are 1.10 Å. In the fourth C+3.33- site, C+3.33- is bonded to one P5+ and three H1+ atoms to form distorted corner-sharing CPH3 tetrahedra. The C–P bond length is 1.79 Å. All C–H bond lengths are 1.10 Å. In the fifth C+3.33- site, C+3.33- is bonded to one P5+ and three H1+ atoms to form distorted corner-sharing CPH3 tetrahedra. The C–P bond length is 1.79 Å. All C–H bond lengths are 1.10 Å. In the sixth C+3.33- site, C+3.33- is bonded to one P5+ and three H1+ atoms to form distorted corner-sharing CPH3 tetrahedra. The C–P bond length is 1.79 Å. All C–H bond lengths are 1.10 Å. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to three C+3.33- and one N3- atom to form corner-sharing PC3N tetrahedra. The P–N bond length is 1.68 Å. In the second P5+ site, P5+ is bonded to three C+3.33- and one N3- atom to form corner-sharing PC3N tetrahedra. The P–N bond length is 1.68 Å. N3- is bonded in a distorted trigonal planar geometry to two P5+ and one H1+ atom. The N–H bond length is 1.05 Å. There are nineteen inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one C+3.33- atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one C+3.33- atom. In the third H1+ site, H1+ is bonded in a single-bond geometry to one C+3.33- atom. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one C+3.33- atom. In the fifth H1+ site, H1+ is bonded in a single-bond geometry to one N3- and one Cl1- atom. The H–Cl bond length is 2.14 Å. In the sixth H1+ site, H1+ is bonded in a single-bond geometry to one C+3.33- atom. In the seventh H1+ site, H1+ is bonded in a single-bond geometry to one C+3.33- atom. In the eighth H1+ site, H1+ is bonded in a single-bond geometry to one C+3.33- atom. In the ninth H1+ site, H1+ is bonded in a single-bond geometry to one C+3.33- atom. In the tenth H1+ site, H1+ is bonded in a single-bond geometry to one C+3.33- atom. In the eleventh H1+ site, H1+ is bonded in a single-bond geometry to one C+3.33- atom. In the twelfth H1+ site, H1+ is bonded in a single-bond geometry to one C+3.33- atom. In the thirteenth H1+ site, H1+ is bonded in a single-bond geometry to one C+3.33- atom. In the fourteenth H1+ site, H1+ is bonded in a single-bond geometry to one C+3.33- atom. In the fifteenth H1+ site, H1+ is bonded in a single-bond geometry to one C+3.33- atom. In the sixteenth H1+ site, H1+ is bonded in a single-bond geometry to one C+3.33- atom. In the seventeenth H1+ site, H1+ is bonded in a single-bond geometry to one C+3.33- atom. In the eighteenth H1+ site, H1+ is bonded in a single-bond geometry to one C+3.33- atom. In the nineteenth H1+ site, H1+ is bonded in a single-bond geometry to one C+3.33- atom. I1- is bonded in a linear geometry to two Cl1- atoms. There are one shorter (2.52 Å) and one longer (2.64 Å) I–Cl bond lengths. There are two inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a 2-coordinate geometry to one H1+ and one I1- atom. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one I1- atom. In each ICl2 cluster, I1- is bonded in a linear geometry to two Cl1- atoms. There are one shorter (2.56 Å) and one longer (2.61 Å) I–Cl bond lengths. There are two inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one I1- atom. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one I1- atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pb3N4 by Materials Project

Pb3N4 is beta Polonium structured and crystallizes in the trigonal R3m space group. The structure is zero-dimensional and consists of three Pb3N4 clusters. Pb4+ is bonded in a 2-coordinate geometry to two equivalent N3- atoms. Both Pb–N bond lengths are 2.43 Å. There are two inequivalent N3- sites. In the first N3- site, N3- is bonded in a T-shaped geometry to two equivalent Pb4+ and one N3- atom. The N–N bond length is 1.34 Å. In the second N3- site, N3- is bonded in a trigonal planar geometry to three equivalent N3- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Combinatorial Exploration and Mapping of Phase Transformation in a Ni–Ti–Co Thin Film Library

Combinatorial synthesis and high-throughput characterization of a Ni–Ti–Co thin film materials library are reported for exploration of reversible martensitic transformation. The library was prepared by magnetron co-sputtering, annealed in vacuum at 500 °C without atmospheric exposure, and evaluated for shape memory behavior as an indicator of transformation. Composition, structure, and transformation behavior of the 177 pads in the library were characterized using high-throughput wavelength dispersive spectroscopy (WDS), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and four-point probe temperature-dependent resistance (R(T)) measurements. A new, expanded composition space having phase transformation with low thermal hysteresis and Co > 10 at. % is found. Unsupervised machine learning methods of hierarchical clustering were employed to streamline data processing of the large XRD and XPS data sets. Through cluster analysis of XRD data, we identified and mapped the constituent structural phases. Finally, composition–structure–property maps for the ternary system are made to correlate the functional properties to the local microstructure and composition of the Ni–Ti–Co thin film library.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Materials Data on SmBiO4 by Materials Project

SmO2BiO2 crystallizes in the triclinic P1 space group. The structure is zero-dimensional and consists of two BiO2 clusters and two SmO2 clusters. In each BiO2 cluster, Bi5+ is bonded in a distorted linear geometry to two O2- atoms. There is one shorter (1.40 Å) and one longer (1.45 Å) Bi–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one Bi5+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one Bi5+ atom. In each SmO2 cluster, Sm3+ is bonded in a distorted bent 120 degrees geometry to two O2- atoms. There is one shorter (1.37 Å) and one longer (1.95 Å) Sm–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one Sm3+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to one Sm3+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Molecular Origin of Nanoscale Anion Ordering of LiTFSI Electrolytes Revealed through SAXS/WAXS and Molecular Dynamics Simulations

Recent developments in “water-in-salt” electrolytes have precipitated a renewed effort to study imide-based electrolytes. While previous small-/wide-angle X-ray scattering (SAXS/WAXS) studies have attributed the emergence of a low-Q peak in the SAXS profile of aqueous LiTFSI electrolytes to nanometer-scale anion clustering, a molecular-level understanding of the root of these clusters remains unclear. Here, in this study, we combined molecular dynamics simulations and SAXS/WAXS to study the solvation structures of LiTFSI in acetonitrile, methanol, and water. We concluded that hydrogen bonding in water and MeOH stabilizes anion clusters, while nonpolar methyl groups on methanol and acetonitrile interrupt the nanoscale ordering of TFSI anions. This causes LiTFSI in water and MeOH electrolytes to exhibit two low-Q SAXS profile peaks while LiTFSI in acetonitrile exhibits only a single peak below Q = 1 Å –1 . These findings shed light on the underlying molecular origins of nanoscale anion clusters, which may help in the design of the next generation of electrolyte chemistries.

Trojanowski, Lucas [Univ. of Michigan, Ann Arbor, ↗
DOE OSTI2020

Materials Data on As2Se3(NF6)2 by Materials Project

N2Se3(AsF6)2 crystallizes in the monoclinic C2 space group. The structure is zero-dimensional and consists of eight AsF6 clusters and four N2Se3 clusters. In each AsF6 cluster, As5+ is bonded in an octahedral geometry to six F1- atoms. There is four shorter (1.77 Å) and two longer (1.78 Å) As–F bond length. There are three inequivalent F1- sites. In the first F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In the second F1- site, F1- is bonded in a distorted single-bond geometry to one As5+ atom. In the third F1- site, F1- is bonded in a distorted single-bond geometry to one As5+ atom. In each N2Se3 cluster, N4+ is bonded in a bent 120 degrees geometry to two Se2- atoms. There is one shorter (1.72 Å) and one longer (1.77 Å) N–Se bond length. There are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 1-coordinate geometry to one N4+ atom. In the second Se2- site, Se2- is bonded in a 2-coordinate geometry to two equivalent N4+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ZnH4(BrO)2 by Materials Project

(ZnBr3)2Zn(H2O)6 crystallizes in the orthorhombic Immm space group. The structure is zero-dimensional and consists of two ZnBr3 clusters and two zinc hexahydrate molecules. In each ZnBr3 cluster, Zn2+ is bonded to four Br1- atoms to form edge-sharing ZnBr4 tetrahedra. There are two shorter (2.43 Å) and two longer (2.48 Å) Zn–Br bond lengths. There are two inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in a single-bond geometry to one Zn2+ atom. In the second Br1- site, Br1- is bonded in an L-shaped geometry to two equivalent Zn2+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on AsXe(OF2)3 by Materials Project

XeO3AsF6 crystallizes in the orthorhombic P2_12_12_1 space group. The structure is zero-dimensional and consists of four AsF6 clusters and four XeO3 clusters. In each AsF6 cluster, As is bonded in an octahedral geometry to six F atoms. There are a spread of As–F bond distances ranging from 1.74–1.81 Å. There are six inequivalent F sites. In the first F site, F is bonded in a single-bond geometry to one As atom. In the second F site, F is bonded in a single-bond geometry to one As atom. In the third F site, F is bonded in a single-bond geometry to one As atom. In the fourth F site, F is bonded in a single-bond geometry to one As atom. In the fifth F site, F is bonded in a single-bond geometry to one As atom. In the sixth F site, F is bonded in a single-bond geometry to one As atom. In each XeO3 cluster, Xe is bonded in a 3-coordinate geometry to three O atoms. There is one shorter (1.86 Å) and two longer (1.93 Å) Xe–O bond length. There are two inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one Xe atom. In the second O site, O is bonded in a single-bond geometry to one Xe atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on TaCl3 by Materials Project

TaCl3 is diamond structured and crystallizes in the cubic Fd-3m space group. The structure is zero-dimensional and consists of eight TaCl3 clusters. Ta3+ is bonded to five Cl1- atoms to form corner-sharing TaCl5 square pyramids. There are one shorter (2.40 Å) and four longer (2.44 Å) Ta–Cl bond lengths. There are two inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one Ta3+ atom. In the second Cl1- site, Cl1- is bonded in a distorted L-shaped geometry to two equivalent Ta3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on H3S by Materials Project

SH3 is High-temperature superconductor structured and crystallizes in the monoclinic Cm space group. The structure is zero-dimensional and consists of two SH3 clusters. there are two inequivalent H+0.33+ sites. In the first H+0.33+ site, H+0.33+ is bonded in a single-bond geometry to one S1- atom. The H–S bond length is 1.48 Å. In the second H+0.33+ site, H+0.33+ is bonded in a single-bond geometry to one S1- atom. The H–S bond length is 1.41 Å. S1- is bonded in a distorted T-shaped geometry to three H+0.33+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2026

Chemical and morphological evolution of hybrid conversion coatings in low-Earth orbit space environment

Understanding how protective coatings respond to the harsh low-Earth orbit (LEO) environment is essential for ensuring the safety, longevity, and cost-effectiveness of spacecraft. In particular, identifying environmentally friendly, non-chromate alternatives that can maintain performance under such conditions has both technological and regulatory significance. This study investigates the environmental stability of zirconium-based hybrid conversion coatings with Cu additives (Cu10 and Cu20) applied to cold-rolled steel, tested in the Materials International Space Station Experiment (MISSE) outside the International Space Station (ISS). Chemical and morphological analyses were carried out using a combination of electron microscopy and X-ray spectroscopy techniques, including scanning electron microscopy (SEM), scanning transmission electron microscopy with energy-dispersive X-ray spectroscopy (STEM-EDS), X-ray photoelectron spectroscopy (XPS), and X-ray absorption near-edge structure (XANES) spectroscopy. After exposure outside the ISS, all coatings remained structurally intact, with all exhibiting a uniform Zr-rich matrix and embedded Cu-rich clusters, while a thin Si-rich surface layer developed from interaction with space environments. Depth-resolved XPS showed a layered structure with CuO on the surface, Cu 2 O, and partial Zr(IV) reduction near Cu-rich sites, evidence of Atomic Oxygen (AO)-driven surface oxidation. These results demonstrate that Cu–Zr coatings maintain their chemical integrity and microstructure in harsh space environments, offering a non-chromate alternative for long-term aerospace protection. These insights provide valuable guidance for developing next-generation protective coatings that combine environmental sustainability with the reliability required for future aerospace and orbital applications.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on IrF6 by Materials Project

IrF6 is beta Np structured and crystallizes in the orthorhombic Pnma space group. The structure is zero-dimensional and consists of four IrF6 clusters. Ir is bonded in an octahedral geometry to six F atoms. All Ir–F bond lengths are 1.88 Å. There are three inequivalent F sites. In the first F site, F is bonded in a single-bond geometry to one Ir atom. In the second F site, F is bonded in a single-bond geometry to one Ir atom. In the third F site, F is bonded in a single-bond geometry to one Ir atom.

36 MATERIALS SCIENCE↗
NASA NTRS1982

The curvature of radio jets and tails in the intracluster media of Abell 1446 and 2220

X-ray observations are reported for two rich clusters which contain prominent tailed radio galaxies. These X-ray data are used as probes of the cluster gas to explore mechanisms which may distort radio jets and tails. A nonrelativistic hydrodynamic flow model is invoked to examine the plasma beam parameters needed to bend the radio streams in a manner consistent with the radio and X-ray data. Within the context of this model, the wide-angle tailed radio structure of 1159 + 583 in A1446 is explained by a combination of a buoyancy pressure gradient in the cluster gas and dynamic pressure arising from slow galaxy motion (200 km/sec). The second cluster observed, A2220, contains a clumped X-ray structure with peaks near two dominant galaxies. The strongly bent radio jets of 1638 + 538 (associated with one of the bright galaxies) are consistent with about 1000 km/sec motion, possibly in a binary orbit, through the X-ray emitting cluster gas; a curved feature in the northern tail, however, may be attributable to buoyancy forces. These X-ray data also suggest that the radio jets and tails are thermally confined by the hot intracluster media.

Burns, J. O.↗